Speed limiter



R. C. HEIDNER July 9, 1957 SPEED LIMITER Filed Oct. 1, 1954 IINVENTOR RmHARDQHEmNER w W41! ATTORNEY United States Patent 2,798,468 SPEED LIMITER Richard C. Heidner, Hartford, Wis., assignor to West Bend Aluminum Co., West Bend, Wis., a corporation of Wisconsin Application October 1, 1954, Serial No. 459,726 4 Claims. (Cl. 123 -98) This invention relates to improvements in control mechanism of internal combustion motors and more particularly to a speed limiter for an outboard motor.

Present day engines of outboard motors are built more and more powerful and develop dangerous high speeds. Such engines are not safe for use by the youngsters in a family and hence they will not have broad application unless they are prevented from developing full speed ca pacity.

It is an object of this invention to provide a speed limiter for an outboard motor or the like which may be adjusted to set a desired upper limit to the motor speed and locked in such position.

Another object is to provide a speed limiting device of a simple and inexpensive construction which is easily adaptable to an outboard motor or the like.

Still another object of this invention is to provide such a speed limiter which is simple and quick in operation and is operable and locked by means of a removable key.

These objects are obtained by using a key operated cam swingable to selected lockable positions. This cam operates a bolt which in turn locks a cam on the motor control rod or limits such cam to swinging only between slow speed position and the selected high speed position.

The novel features which are considered characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and its method of operation together with' additional objects and advantages thereof will best be understood from the following description of a specific embodiment when read in connection with the accompanying drawings, in which:

Fig. 1 is a view partly in section and partly in side elevation of a speed limiter embodying the present invention attached to an outboard motor, the motor support, cover and tiller being shown in fragmentary view:

Fig. 2 is a view in elevation of such speed limiter taken from the line 22 of Fig. l; and

Fig. 3 is a fragmentary view in front elevation of the lock of such speed limiter taken from the line 3-3 of Fig. 1.

It is customary to control the speed of an outboard motor by advancing or retarding the stator of the magneto and at the same time opening or closing the throttle of the carburetor. Such joint control may be accomplished by the rotation of the handle of a tiller which is connected in well-known manner to the control rod, the rotation of which controls the position of both the magneto and the throttle. The speed limiter in this embodiment is shown operable on the control rod of an outboard motor having a support 12, instrument panel 14, tiller 16, and top 18.

Referring to the drawings, the speed limiter includes lock mounted in the panel 14 to which is secured a cam 22 which can be rotated by the turning of a key 24 when inserted into the lock. Upon removal of the key at any of the locked stations indicated, the cam 22 can not be rotated. The key 24 is inserted from the outside of the 2,798,468 Patented July .9, 1957 panel 14. Within the motor housing themotor control rod 10 is rotatably mounted in a bracket 26 carried on the support 12. Adjacent this bracket, there is secured to the control rod a second cam 28. In this exemplification there are four locked positions for the cam 22: oif, 5 H. P., 7. 5. H. P., and max. H. P. (see Fig. 3). The'cam 22 is shown in off position with an off notch 30 in the nose at 6 oclock. Upon rotating the key 24 clockwise in steps at 5 H. P. notch 32, a 7 /211. P. notch 34 and a max. H. P. notch 36 will be successively brought into the active 6 oclock position. The control rod cam 28 is shown with an ofiflocking notch 38 at 12 oclock. In this position of the control rod 10 the motor is shorted and can not be started. As the control rod is rotated clockwise at 90 steps, a 5 H. P. tooth 40 and a 7 /2 H. P. tooth 42 are respectively brought into the 12 oclock position. A push rod 44 slidably supported in hearings in the bracket 26 and in a spaced bracket 46 secured to the panel 14 extends between the cams 22 and 28 so as to lock or limit block the cam 28 under influence of the cam 22. A spiral spring 48 around the push rod 44 between the bracket 26 and a transverse stud 50 produces a continuous upward tension on the rod to keep its upper end in close contact with the cam 22 and the notches therein.

The upper end of the push rod 44 can be nested in notch 30 only when the locking notch 38 is brought into alinement. This position shown in the drawings locks the motor control in 01f position. By turning the key 24 to 5 H. P. the upper end of rod 44 is raised and comes to rest in the notch 32. There is enough clearance between the lower end of the rod 44 and bottom of notch 38 to allow the edge of notch 30 to pass over the top end of such rod. In the 5 H. P. position of cam 22, cam 28 may be freely rotated between off notch 38 and 5 H. P. tooth 40. Thus the motor can be operated at speeds determined by the thus limited horse-power. By turning the key to the 7 /2 H. P. position, the rod 44 is raised so that its lower end will clear tooth 40 and engage the 7 /2 H. P. tooth 42. This permits the motor control rod 10 to be operated within the 7% H. P. range but the motor cannot go over the speeds obtained from the thus limited horse-power. By turning the key 24 to max. H. P. position the rod 44 raises to the maximum position permitted by notch 36 and the 7 /2 H. P. tooth 42 will clear the lower end of such rod permitting use of the control rod 10 throughout the entire range thereof. As it is shown in Fig. 3, indicia such as 01f, 5 H. P., 7.5 H. P., max. H. P. surround the lock 20 to permit easy positioning of the key 24. When the speed limiter is adjusted to a selected position and the key is removed, no further adjustment can be made.

Although only one embodiment of the invention is shown and described herein, it will be understood that this application is intended to cover such other changes or modifications as come within the spirit of the invention or scope of the following claims.

I claim:

1. A speed limiting mechanism for a motor having a rotatable control rod comprising, rotatable first cam, locking means for mounting, adjusting and locking said cam, a second cam rigidly mounted on said control rod, and a cam rod slidably positioned with its ends in operable relation to said cams, said first cam having surfaces limiting the longitudinal movement of said rod, said second cam having shoulders on its rotating surface engageable with said cam rod to limit the amplitude of the rotative movement of said control rod.

2. A speed limiting mechanism as claimed in claim 1 in which said locking means includes a rotatable key for rotating said first cam, said key being removable at a plurality of cam positions to lock said first cam in a selected one thereoftolimit the top speed of said motor.

3. In combination an outboard motor having a speed control member, a rotatable key controlled lock, indicia meansassociatedwithsaid lock determining the positions thereof, a key for 'rotatingand locking said lock in position, said" key and indicia means being simultaneously visible whereby said keymay, be aliued'with said indicia to select' a position; first abutment means adjustable by rotation of said lock, and second abutment means as- 10 sociated with said-speed control member, said first abutment meansbeing operably' associated with said second abutment means tolimit the'movement thereof in the speed increasing direction of said speed control'mem-berwhile 1 150 162 permittingsaid second abutment means to freelymove 15 1181571 between'low speed position and saidfirst-abutment means.

References: Cited in the file of this patent UNITED STATES PATENTS' 1,000,523 Illsley Aug. 15, 1911 Arnold Aug. 17, 1915 C'onl'ey May 2, 1916 

